/Engine/Source/Runtime/Core/Public/Math/TransformNonVectorized.h
Inverse transform a rotation. For example if this is a LocalToWorld transform, InverseTransformRotation(Q) would transform Q from world to local space.
[TQuat](API\Runtime\Core\Math\TQuat)< T > InverseTransformRotation ( const [TQuat](API\Runtime\Core\Math\TQuat)< T > & Q ) const